The electron multiplier and photomultiplier are well known in the art, as disclosed, for example, in Japanese published examined patent application No. SHO-56-1741. The photomultiplier disclosed in Japanese published examined patent application No. SHO-56-1741 includes a plurality of metal plates (dynodes) in which is formed a plurality of electron multiplying holes for multiplying electrons injected therein. A glass layer is formed across the surface of the output end or input end on the metal plates. The metal plates are stacked together with the glass layers interposed therebetween.
However, since a glass layer is formed across the entire output end or input end surface of the metal plates (dynodes) in the photomultiplier described above, warping can occur in the metal plate due to a difference in the thermal expansion coefficients of the metal plates and the glass layers, thereby making it difficult to stack the metal plates.